To prepare the chicken
Rinse the chicken (inside and out) in cold water, pat dry. Remove the backbones and flatten from the breast side.
Grate the lemon zest, set aside for the gremolata, squeeze out the juice. Combine the lemon juice, beer and maple syrup. Coat the chicken with half of the marinade, cover and leave to marinate in the fridge for approx 1 hr.
Wipe the marinade from the chicken and season with salt. Charcoal/gas/electric grill: Cook the chicken over/on a medium heat (approx. 150 °C for approx. 1 hr., turning from time to time and coating with the remaining marinade.
Mix the parsley, garlic and reserved lemon zest, season. Serve with the chicken.